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Lactose is a disaccharide that consists of a galactose unit and a glucose unit bonded together with a β glycosidic linkage. The glucose unit can exists in one of two isomeric hemiacetal forms as well as in a free aldehyde form. The isomeric hemiacetal forms, beta and alpha lactose, are anomers because the hemiacetal hydroxyl group gives diasteromeric products at the anomeric carbon.
Alpha and beta-lactose are able to change back and forth because of mutarotation, which is the change in specific rotation. The rate of this interchanging is influenced by a number of conditions including: the concentration of lactose, the temperature and the acidity, or pH, of the milk. At room temperature, the ratio of isomers is about 40% alpha to 60% beta.
The solubility of the two anomers is temperature dependent and therefore the equilibrium concentration of the 2 forms will be different at different temperatures. At room temperature (70°F, 20°C) the equilibrium ratio is approximately 37% α- and 63% ß-lactose. At temperatures above 200°F (93.5°C) the ß-anomer is less soluble so there is a higher ratio of α- to ß-lactose. The type of anomer present does not affect the nutritional properties of lactose.
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Do lipid soluble molecules diffuse into a cell more rapidly than water soluble molecules?
Yes.
What is the sensor and integrator and effector of the blood glucose feedback loop?
The sensor in a negative feedback loop monitors the state of the variable, in this case blood glucose. For blood glucose, the sensor as well as the integrator is the Islets of Langerhans, since it contains the alpha and beta cells. Alpha cells produce glucagon, a hormone that acts on the liver to release more glucose into the blood. Beta cells produce insulin, which controls the uptake of glucose into the cells. The effectors respond to the sensor's messages, and act to maintain a variable. The effectors for blood glucose are the cells which take in glucose, as well as the liver.
What is a tertiary protein structure exemplified by?
Hemoglobin - formed with alpha helices and/or beta sheets, but as one, contiguous polypeptide. Superoxide dismutase would be a good example of a quaternary structure protein, since it is made of more than one polypeptide chain.
What bacteria are non-lactose ferment er?
Mnemonic: KEE Klebsiella pneumoniae Enterobacter cloacae E. coli Shigella sonnei can ferment lactose, but only after prolonged incubation and so it is referred to as a '''''late-lactose fermenter'''''. Vibrio cholerae is also a late lactose fermenter.
What two characteristics tend to make lipids more soluble?
short chain and unsaturated
Which is more stable alpha or beta glucose?
beta glucose
Which is better mine craft alpha or beta?
Minecraft Beta is better than Minecraft Alpha. If you want more Beta and more Alpha versions. Donate to mojang, so I can tell the creators to create, create more versions.
Equation for the formation of alpha d-lactose from beta d-galactose and alpha d-glucose?
The general formula is (CH2O)n (simple sugars) or Cx(H20)y. It can get more complexed though, but it all depends on what you are trying to do.
Which is better alpha testing or beta testing?
alpha. it's a more private testing.
What is the range of beta particles in air as compare to alpha particles?
What is the range of beta particles in air as compare to alpha particles?Read more: What_is_the_range_of_beta_particles_in_air_as_compare_to_alpha_particles
How does the penetrating ability of gamma rays compare with that of alpha particles and beta particles?
Gamma rays are more penetrating than alpha and beta particles.
Which has the largest mass alpha particle gamma ray positron or beta particle?
The alpha particle is much more massive than a beta particle. A beta particle is an electron, which has very little mass. An alpha particle is a helium nucleus, and consists of two protons and two neutrons.
If the mixture of electrically neutral how many more beta particles than alpha particles are in the balloon?
alpha particles would have twice as many beta particles
Which is more stable alpha-fructose of beta-fructose?
Beta is more stable. It is in the equatorial position. When glucose is in monomeric form this does not matter much but when polymerized. Alpha produces starch (OH Down) and Beta produces cellulose (OH UP).
Why do alpha and beta particles cause more damage if they are inside the?
Because alpha and beta particles do not have enough power to pass into the body, but they do more damage than gamma rays once they are inside the body.
Why were a few alpha particles reflected at large angles?
yes it is
Why are reactions that emit alpha particles generally considered more safe than those that emit beta particles?
Alpha particles are actually electron-less helium nuclei versus beta particles which are actually electrons, which are much smaller than alpha particles. Therefore, alpha particles' penetrating strength is much smaller than beta particles (a sheet of paper versus a wooden board). Therefore, beta particles will penetrate more into a human body and will do more damage than alpha particles which are usually stopped at the skin.
